Solid-state imaging device and electronic apparatus
The present technology relates to a solid-state imaging device and an electronic apparatus that realize a high frame rate image capture without deteriorating an image quality. A floating diffusion holds a charge accumulated on one or more photoelectric conversion units. A plurality of amplification transistors read out a signal corresponding to the charge held by the floating diffusion. The signal read out by the amplification transistor is output to a vertical signal line. The plurality of amplification transistors are connected in parallel. The present technology is applicable to a CMOS image sensor, for example.
1. A solid-state imaging device, comprising:
at least one photoelectric conversion unit configured to accumulate charge;
a floating diffusion configured to hold the charge accumulated on the at least one photoelectric conversion unit;
a plurality of amplification transistors configured to read out a signal corresponding to the charge held by the floating diffusion, wherein the plurality of amplification transistors are connected in parallel;
a vertical signal line configured to receive the signal read out by the plurality of amplification transistors;
at least one selection transistor configured to output the signal read out by the plurality of amplification transistors to the vertical signal line,
wherein a count of the at least one selection transistor is equal to or less than a count of the plurality of amplification transistors, and
wherein a first threshold voltage of the at least one selection transistor is set lower than a second threshold voltage of the plurality of amplification transistors.
2. The solid-state imaging device according to claim 1 ,
wherein the plurality of amplification transistors are connected to the vertical signal line via the at least one selection transistor.
3. The solid-state imaging device according to claim 2 , further comprising a load transistor connected to the vertical signal line, wherein
a first on-resistance of the load transistor is set smaller than a sum of a second on-resistance of the plurality of amplification transistors and a third on-resistance of the at least one selection transistor.
4. The solid-state imaging device according to claim 3 , wherein
the first on-resistance of the load transistor is set smaller than the sum of the second on-resistance of the plurality of amplification transistors and the third on-resistance of the at least one selection transistor based on a specific threshold voltage of the load transistor.
5. The solid-state imaging device according to claim 3 , wherein
the first on-resistance of the load transistor is set smaller than the sum of the second on-resistance of the plurality of amplification transistors and the third on-resistance of the at least one selection transistor based on a specific threshold voltage of the plurality of amplification transistors.
6. The solid-state imaging device according to claim 3 , wherein
the first on-resistance of the load transistor is set smaller than the sum of the second on-resistance of the plurality of amplification transistors and the third on-resistance of the at least one selection transistor based on a specific load current value of the load transistor.
7. The solid-state imaging device according to claim 1 , wherein
the plurality of amplification transistors are on an identical active region.
8. The solid-state imaging device according to claim 1 , wherein
the plurality of amplification transistors are on different active regions, and
an element separation region is between the different active regions.
9. An electronic apparatus, comprising:
a solid-state imaging device, including
at least one photoelectric conversion unit configured to accumulate charge,
a floating diffusion configured to hold the charge accumulated on the at least one photoelectric conversion unit,
a plurality of amplification transistors configured to read out a signal corresponding to the charge held by the floating diffusion,
wherein the plurality of amplification transistors are connected in parallel,
a vertical signal line configured to receive the signal read out by the plurality of amplification transistors,
at least one selection transistor configured to output the signal read out by the plurality of amplification transistors to the vertical signal line,
wherein a count of the at least one selection transistor is equal to or less than a count of the plurality of amplification transistors, and
wherein a first threshold voltage of the at least one selection transistor is set lower than a second threshold voltage of the plurality of amplification transistors.
10. A solid-state imaging device, comprising:
at least one photoelectric conversion unit configured to accumulate charge;
a floating diffusion configured to hold the charge accumulated on the at least one photoelectric conversion unit;
a plurality of amplification transistors configured to read out a signal corresponding to the charge held by the floating diffusion,
wherein the plurality of amplification transistors are connected in parallel;
a vertical signal line configured to receive the signal read out by the plurality of amplification transistors;
at least one selection transistor configured to output the signal read out by the plurality of amplification transistors to the vertical signal line,
wherein a count of the at least one selection transistor is equal to or less than a count of the plurality of amplification transistors,
wherein the plurality of amplification transistors are connected to the vertical signal line via the at least one selection transistor, and
wherein a first threshold voltage of the at least one selection transistor is set lower than a second threshold voltage of the plurality of amplification transistors; and
a load transistor connected to the vertical signal line,
wherein a first on-resistance of the load transistor is set smaller than a sum of a second on-resistance of the plurality of amplification transistors and a third on-resistance of the at least one selection transistor.